The present invention relates to collimating lenses.
Laser beams inherently have Gaussian intensity profiles and, if the laser source is a semiconductor device, the beam is highly divergent. There is a need for a simple single optical element for performing collimation of the divergent beam and at the same time, redistributing the light beam passing through the optical element from a Gaussian to a uniform intensity profile.
In the past, collimation and redistribution of light intensity have been performed with separate optical elements. Collimation of highly divergent sources required the fabrication of expensive, complicated, aspherical lenses. Also, the beam had to be collimated before intensity redistribution could take place. Additional expensive asphical lenses had to be provided. Computer generated holograms have also been constructed to perform redistribution. Two holograms were provided which are inefficient, and much of the input light intensity was lost due to this inefficiency.